Microsoft Office

Part VI
Programming Excel with VBA
A function with two arguments
This example builds on the previous one. Imagine that the sales manager implements a new policy: The
total commission paid is increased by 1 percent for every year that the salesperson has been with the company.
For this example, the custom Commission function (defined in the preceding section) has been
modified so that it takes two arguments, both of which are required arguments. Call this new function
Commission2:
Function Commission2(Sales, Years)
‘ Calculates sales commissions based on years in service
Tier1 = 0.08
Tier2 = 0.105
Tier3 = 0.12
Tier4 = 0.14
Select Case Sales
Case 0 To 9999.99
Commission2 = Sales * Tier1
Case 1000 To 19999.99
Commission2 = Sales * Tier2
Case 20000 To 39999.99
Commission2 = Sales * Tier3
Case Is >= 40000
Commission2 = Sales * Tier4
End Select
Commission2 = Commission2 + (Commission2 * Years / 100)
End Function
The modification was quite simple. The second argument (Years) was added to the Function statement,
and an additional computation was included that adjusts the commission before exiting the function.
The following is an example of how you write a formula by using this function. It assumes that the sales
amount is in cell A1, and that the number of years that the salesperson has worked is in cell B1.
=Commission2(A1,B1)
A function with a range argument
The example in this section demonstrates how to use a worksheet range as an argument. Actually, it’s not at
all tricky; Excel takes care of the details behind the scenes.
Assume that you want to calculate the average of the five largest values in a range named Data. Excel doesn’t
have a function that can do this calculation, so you can write the following formula:
=(LARGE(Data,1)+LARGE(Data,2)+LARGE(Data,3)+
LARGE(Data,4)+LARGE(Data,5))/5
This formula uses Excel’s LARGE function, which returns the nth largest value in a range. The preceding formula
adds the five largest values in the range named Data and then divides the result by 5. The formula
works fine, but it’s rather unwieldy. And, what if you need to compute the average of the top six values?
You’d need to rewrite the formula and make sure that all copies of the formula also get updated.
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